A woman crosses an open sewer as she makes her way to her house in a Christian slum in Islamabad December 4, 2014. (Photo by Zohra Bensemra/Reuters)

Maya, 8, and Kishore, 13, pose for a wedding photo inside their new home, the day after the Hindu holy day of Akshaya Tritiya, called Akha Teej in North India. Despite legislation forbidding child marriage in India (Child Marriage Restraint Act-1929) and the much more progressive Prohibition of Child Marriage Act (2006) and many initiatives to prevent child marriage, marrying children off at a very tender age continues to be accepted by large sections of society. (Photo by Stephanie Sinclair/VII Photo Agency)

Fisherwomen laying barrels with salt in preparation for herring curing, 1937. (Photo by Topical Press Agency)

Dancers perform on stage during Diwali celebrations in Leicester, Britain November 11, 2015. (Photo by Darren Staples/Reuters)

An American family with a carved pumpkin illuminated by a candle to celebrate Halloween. (Photo by Sherman/Three Lions/Getty Images). Circa 1955

Revellers from Russia parade during the Aoussou Carnival in Sousse, Tunisia July 26, 2015. (Photo by Anis Mili/Reuters)

A woman presents an Afro-Colombian hairstyle during the 9th contest of Afro-hairdressers, in Cali, Valle del Cauca departament, Colombia, on May 12, 2013. The Afro hairstyles have their origins in the time of slavery, when women sat to comb their children hair after work. (Photo by Luis Robayo/AFP Photo)

A family poses for a picture in front of the carcasses of sacrificed buffalos a day after the sacrificial ceremony of the “Gadhimai Mela” festival held in Bariyapur November 29, 2014. Sword-wielding Hindu devotees in Nepal began slaughtering thousands of animals and birds in a ritual sacrifice on Friday, ignoring calls by animal rights activists to halt what they described as the world's largest such exercise. (Photo by Navesh Chitrakar/Reuters)